The invention relates to a pouch container suitable for containing a food product. The invention especially relates to flexible ‘stand up’ pouches for the storage and subsequent heating of food product.
Packaging pouches are increasingly widespread for food use, especially in that they offer a convenient and compact dual use solution both as a storage receptacle and as a receptacle for heating of food. Such pouches in particular relate to prepared or partially prepared food product, and in particular to previously raw, partially or completely cooked food, which is sealed in a pouch for storage. Such pouches are especially useful for product that is subsequently reheated prior to use for example in a microwave, in a pan of boiling water, or via any other suitable heat source.
Pouches of this type in particular find application as retortable pouches for room temperature storage of product, where food product, and in particular cooked food product is sealed within a flexible pouch, is then retorted to sterilise the product to allow room temperature storage, and is subsequently reheated for example by boiling in water or in a microwave. However, such technology also finds application in relation to product stored in a chilled or frozen state. Again, food product, and in particular raw or pre-cooked food product, is sealed within a flexible pouch, which is then either kept chilled or frozen to maintain shelf life. In such circumstances, there is no requirement for the pouch to be retorted to sterilise the contents, since preservation is via the chilling or freezing process, but further thermal processing to pasteurise the food may be made in pack to extend shelf life.
However, a broadly similar range of packaging technologies can be employed with pouches that are intended for a retort-based or other heat-based sterilisation treatment and with pouches that are intended for other shelf-life preservation techniques such as freezing, chilling, or the like. Where the term “retortable pouch” is used herein, or where exemplification of the invention is given in the context of such retortable pouches, it is to be understood that such use is intended generally to cover all food product pouch packaging of the basic design that is suitable both for heat-treatment sterilisation processes for room temperature storage and for chilled or frozen storage, pasteurisation or the like. References are to be construed accordingly.
The term “food product” is similarly to be interpreted broadly to cover any ingestible product whether solid, liquid, fluid or combination thereof, although for the reasons below the invention particularly relates to packing for a food product including a solid and a fluid component.
Pouches of the type described suffer from a particular drawback. While they can offer adequate safe shelf life, either through a sterilisation process or through chilled or frozen storage or another suitable preservation process, certain food components cannot be mixed within the pouch without deterioration of eating quality. A number of food products, in particular starchy food products such as rice, pasta, noodles, starchy pulses, vegetables and the like, and also essentially dry food products, are prone to lose texture quite rapidly through liquid absorption if they are kept in a state where there is an excess of liquid. However, most food products involving the likes of pasta, rice, potatoes etc. will necessarily comprise a recipe with a liquid component, such as a sauce or the like in order to be palatable and desirable.
These issues have tended to limit the use of single flexible pouches for such meal products, and instead have tended to favour the use of separate pouches for separate products, or at least to keep the liquid part such as a sauce separate from the starchy part such as pasta, rice or potatoes, or to favour the use of multiple compartment rigid trays. In either instance, the different components are kept separate during storage and are effectively cooked entirely separately.
In an attempt to address this potential limitation of conventional pouches it has been suggested that multiple compartmental pouches may be provided. For example, WOO 1/21506 describes a dual compartment food package for microwave cooking in which an internal pouch contains the fluid substance, and an external carton contains both the internal pouch and dry food substance, with the internal pouch designed to burst during heating.
Such systems are not ideal. In a simple state, they are likely to burst in an uncontrollable manner, and there is possibility of the debris from the burst contaminating the food. If zones of weakness, for example comprising parts that melt or burst preferentially, are built into the packaging, those melt or burst residues can still present a contamination issue. This lack of controllability, and tendency to contamination, arising in such designs has tended to limit their effectiveness and favour designs which are fully separate and compartmentalised keeping liquid components separate from those components where an excess of liquid is undesirable during storage and, in the instance where the containers are dual use as cooking receptacles also, separate during cooking with mixing prior to serving.